Walk into any gym and watch people train their hamstrings. Try not to be all creepy about it. What's the go-to exercise for hammies? It's the lying leg curl machine.

Leg Curl

It's not a bad exercise either. But is it the best? Researchers decided to find out.

The Study

Sixteen lifters were recruited for this study, eight women and eight men. The researchers had them do several different hammy exercises:

  • Lying Leg Curl Machine
  • Seated Leg Curl Machine
  • Romanian Deadlift (barbell)
  • Single-Leg Romanian Deadlift (dumbbell)
  • Glute-Ham Raise Machine
  • Bodyweight Glute-Ham Raise (Nordic Curl)
  • Kettlebell Swing
  • Stability Ball Hamstring Curl
  • Reverse Hip Raise (Reverse Hyper)

Subjects were strapped up with surface electrodes to test their levels of muscle activation. Weights used were 70 percent of 1RM.

Several other sciency things were tested too, but let's not make this boring and instead jump right to...

The Results

The kettlebell swing slightly outperformed the lying leg curl when it came to biceps femoris activation. The heavy black line in the chart represents the lying leg curl:

Hamstring Chart

The other measurable muscle in the hamstring group, the semitendinosis, was tested too. In this case, stability ball hamstring curls, reverse hypers, and bodyweight GHRs outperformed the lying leg curl machine.

Semitendinosis Chart

The amateur anatomists might be screaming right now because the third hamstring muscle, the semimembranosus, wasn't tested. But the REAL anatomy geeks know that you can't put an EMG electrode on the deep semimembranosus, and it's tough to isolate anyway.

What This Means to You

The lying leg curl machine is great, but don't freak out if someone else is already using it. Do the kettlebell swing and pair it with stability ball hamstring curls, reverse hypers, or bodyweight GHRs (Nordics).

Related:  Fix Your Squatty Kettlebell Swing

Related:  The Absolute Best Way to Build Your Hamstrings

Source

  1. American Council on Exercise, Kayla Schmitt, B.S., John P. Porcari, Ph.D., Clayton Camic, Ph.D., Attila Kovacs, Ph.D., and Carl Foster, Ph.D., with Daniel J. Green